Minerals and Rocks
THERMAL PROPERTIES
Heat flow (or
flux), q, in the
Earth's crust or in rock as a building material, is the product
of the temperature gradient (change in temperature per unit
distance) and the material's thermal conductivity (k,
the heat flow across a surface per unit area per unit time when
a temperature difference exists in unit length perpendicular
to the surface). Thus,
The units of the terms in this equation are given below, expressed
first in the centimetre-gram-second (cgs) system and then in
the International System of Units (SI) system, with the conversion
factor from the first to the second given between them.
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